Development of in-situ sensors for direct quantification of metal speciation and bio-availability

环境中的金属对生命形式至关重要，因此被视为微量营养素，但当过量存在时，它们可能有毒。目前对生物群可利用金属的测量和评估对于优化农业和水产养殖以及评估生态和人类健康至关重要。有机体对金属的吸收是复杂的，取决于金属的各种化学形式的交换动力学。一种测量工具要成功地评估金属的生物可利用形态，它必须模拟生物群的基本特征。薄膜扩散梯度（DGT）的新技术模拟了动力学的某些方面，但它缺乏生物体的一些基本特征。这项工作将引入可控的生物特征到DGT中，以提供两种新的工具，可用于原位评估生物可利用金属。生物结合DGT （BBDGT）将纳入细胞培养，以实现从溶液中摄取的精确模拟。生物动员DGT （BMDGT）将包含微生物成分，可以测量能够从胶体和颗粒中释放的金属。

Metals in the environment can be essential to life forms and so are regarded as micronutrients, but when excessive amounts are present they may be toxic. Current measurement and assessment of the metal that is available to biota is essential for optimising agriculture and aquaculture and for assessing ecological and human health. The uptake of metals by organisms is complicated and depends on the dynamics of exchange of the various chemical forms of the metal. For a measurement tool to assess successfully the bioavailable forms of the metal it must mimic the essential characteristics of the biota. The new technique of diffusive gradients in thin-films (DGT) emulates some aspects of the dynamics, but it lacks some essential features of the organism. This work will introduce controlled biological features into DGT to provide two new tools that can be used in situ to assess bioavailable metals. The biological binding DGT (BBDGT) will incorporate cell cultures to enable precise mimicry of uptake from solution. The biological mobilising DGT (BMDGT) will contain microbial components that can enable the measurement of metals capable of release from colloids and particles.